Concepts Of Physics MCQ Edition [Volume 2]PhysicsMagnetic Field due to a Current
Examine the scenario illustrated in the figure. The straight wire is kept fixed, whereas the loop is free to move under the influence of magnetic force. As a result, the loop will
Options
- Amove away from the wire
- Bmove towards the wire
- Crotate about the wire
- Dremain stationary
Correct answer
B. move towards the wire
Step-by-step solution
The magnetic field due to the straight wire carrying current i₁ is directed into the plane of the paper at the location of the loop. The magnetic forces on the top and bottom horizontal segments of the loop are equal in magnitude and opposite in direction, cancelling each other out. The left vertical segment carries current in the same direction as the straight wire. Parallel currents attract, so it experiences an attractive force F₁ towards the wire. The right vertical segment carries current in the opposite direc